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Effectiveness of HPV Vaccine in Thai Adult Women

Completed
Conditions
Uterine Cervical Dysplasia
Papillomavirus Vaccines
Interventions
Biological: Bivalent or Quadrivalent HPV vaccines
Other: Control group
Registration Number
NCT03763565
Lead Sponsor
Mahidol University
Brief Summary

* Background: The majority of the burden of HPV-related cervical cancer is in developing countries while most of the effectiveness reports of HPV vaccination are currently coming from developed countries. Also, currently many adult women are left without either HPV vaccination or cervical cancer screening. Effectiveness data of currently available HPV vaccines among adult women in developing countries are needed for women and healthcare workers and policy makers to best protect women from cervical cancer.

* Primary Study Objective:

- To determine the effectiveness bivalent and quadrivalent HPV vaccines in reduction of cervical dysplasia (Low-grade Squamous Intraepithelial Lesion or worse; LSIL+) attributable to HPV types 16 or 18 after at least 5 years of vaccination among Thai women vaccinated at their ages 20-45 years with at least one dose of the HPV vaccine

* Secondary Study Objectives:

* To measure the effectiveness of currently available bivalent and quadrivalent HPV vaccines in reducing the prevalence of HPV 16 or 18

* To measure the effectiveness of HPV vaccines in reducing any abnormal Pap smear result (ASC-US+)

* To compare the effectiveness of HPV vaccines according to the number of doses immunized

* To find out risk factor(s) for HPV 16 or 18-related cervical dysplasia in this cohort

* To assess the prevalence of other high-risk HPV types in vaccinated and non-vaccinated group

* To determine direct and/or indirect cost of HPV vaccination

* The hypothesis to be tested: At least one dose of vaccination with bi- or quadri-valent HPV vaccine will reduce the prevalence of LSIL+ attributable to HPV 16/18 by 80% after at least 5 years of vaccination.

* Materials and Methods: This study will be a retrospective matched cohort study. Data is to be collected either by from samples for Pap and HPV test and/or HPV 16/18 genotyping of the recruited participants, or from existing medical records. HPV vaccinated women at their ages 20-45 years (vaccinated group) and women received Pap smear at their ages 20-45 years without vaccination (control group) will be included in the study. Pap smear and HPV test and/or HPV 16/18 typing result of 2 groups will be compared after ≥ 5 years of vaccination or baseline Pap smear. Those who don't have Pap smear results ≥ 5 years after vaccination or ≥ 5 years after the baseline Pap smear will be offered for a Pap smear and HPV 16/18 typing

Detailed Description

Not available

Recruitment & Eligibility

Status
COMPLETED
Sex
Female
Target Recruitment
993
Inclusion Criteria

Not provided

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Exclusion Criteria
  • Known pregnancy
  • History of hysterectomy or excisional treatment of the cervix
  • Known increased risk of bleeding
  • Not willing to provide written informed consent
Read More

Study & Design

Study Type
OBSERVATIONAL
Study Design
Not specified
Arm && Interventions
GroupInterventionDescription
Vaccinated groupBivalent or Quadrivalent HPV vaccinesThai women who received at least one dose HPV vaccination at least 5 years ago, either by Bivalent or Quadrivalent HPV vaccines when they were 20-45 years old
Control groupControl groupThai women who did not receive HPV vaccination, either by bivalent or quadrivalent HPV vaccine but have received Pap smear at their ages 20-45 years at least 5 years ago from the current enrollment time
Primary Outcome Measures
NameTimeMethod
Occurrence of Low-grade squamous intraepithelial lesion or worse (LSIL+) associated with HPV 16 or 18Sample collection in the project is single 1 day time for participants who received vaccination at least 5 years ago.

LSIL or worse, including Atypical Glandular Cells, High-grade squamous intraepithelial lesion, Cervical intraepithelial neoplasia (CIN) grade 1-3, and cervical cancer which are associated with either HPV 16 or 18

Secondary Outcome Measures
NameTimeMethod
Cost-effectiveness of bivalent and quadrivalent HPV vaccinationInterview for direct and indirect cost survey will be single 1 day time for a participant.

Direct and and indirect cost survey interview associated with HPV vaccination and its cost-effectiveness

Trial Locations

Locations (5)

Vaccine Trial Centre, Faculty of Tropical Medicine, Mahidol University,

🇹🇭

Bangkok, Thailand

Bumrungrad International Hospital

🇹🇭

Bangkok, Thailand

King Chulalongkorn Memorial Hospital

🇹🇭

Bangkok, Thailand

Siriraj Hospital, Mahidol University

🇹🇭

Bangkok, Thailand

National Cancer Institute, Thailand

🇹🇭

Bangkok, Thailand

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